1. Technical Field
The present invention relates to a power distributor placed on a vehicle, and a method for connecting a control circuit board to the power distributor, the control circuit board containing a built-in control circuit or the like.
2. Related Art
An electric connect box having fuses and relay switches incorporated in a power distribution circuit constituted by a laminate of a plurality of bus bar boards is generally known as a power distributor for distributing electric power given from an on-vehicle power supply into a plurality of on-vehicle loads. Further, to add a high-level function such as high-speed switching control or the like to the power distributor, a control circuit board having various kinds of electronic circuit devices mounted thereon is connected to the bus bar board and is housed together with the bus bar board in a housing.
As means for connecting the control circuit board to the bus bar board, there is known a method in which tab terminals formed by bending and raising end portions of bus bars are inserted into through-holes provided in a printed circuit board and electrically connected to a circuit of the printed circuit board by soldering or the like. In this method, it is however necessary to punch out a metal plate into a shape inclusive of the tab terminals as the bus bars. Hence, the bus bar area increases correspondingly and, accordingly, the final board area increases to thereby disturb reduction in size. There is also a disadvantage that it is difficult to align the position of each tab terminal with the position of a corresponding board-side through-hole accurately.
Therefore, a technique of connecting a control circuit board to the bus bars through a flexible wiring material such as a flexible printed circuit (FPC) or the like and receiving the control circuit board in a housing while bending the flexible wiring material suitably has been advanced in recent years (for example, see the Unexamined Japanese Patent Application Publication No. Hei8-251763).
3. Problem to be Solved
When the control circuit board is to be connected to the bus bar board, there is needed the step of positioning the control circuit board relative to the bus bar board accurately while holding the control circuit board near the bus bar board by use of a jig or a robot. The step is complex and becomes a big barrier to reduction in cost.
As means for simplifying such a complex step, there is conceived of means of connecting the control circuit board to the bus bar board after fixing the control circuit board to a predetermined receiving position in the housing. Although it is general from the point of view of reduction in total size of the power distributor that the control circuit board is received in the housing in the condition that the control circuit board is toppled over approximately in parallel with the bus bar board, it is, however, very difficult to connect the control circuit board to the bus bar board through the flexible wiring material in the condition that the control circuit board is toppled over.
The present invention is devised upon such circumstances and an object of the invention is to provide a vehicle power distributor in which a control circuit board can be electrically connected, by a simple step, to a power distribution circuit constituted by conductor plates such as bus bars or the like, and to provide a method of connecting a control circuit board to the power distributor.
As mean for solving the problem, according to the present invention, there is provided a vehicle power distributor comprising a power distribution circuit constituted by conductor plates, and a housing for receiving the power distribution circuit, the housing having a space secured for receiving a control circuit board connected to the power distribution circuit in a state in which the control circuit board is toppled over approximately in parallel with the conductor plates, wherein a board support portion for supporting the control circuit board in an erect posture with respect to the conductor plates is provided near the conductor plates so that the control circuit board can be connected to the conductor plates through a flexible wiring material in a condition that the control circuit board is supported by the board support portion (Aspect 1).
Further, according to the present invention, there is provided a method of connecting a control circuit board to a vehicle power distributor having a power distribution circuit constituted by conductor plates, and a housing for receiving the power distribution circuit, the housing having a space secured for receiving a control circuit board connected to the power distribution circuit in a state in which the control circuit board is toppled over approximately in parallel with the conductor plates, the method comprising the steps of: connecting the control circuit board to the conductor plates through a flexible wiring material in a state where the control circuit board is supported in an erect posture by aboard support portion which is provided near the conductor plates for supporting the control circuit board in an erect posture with respect to the conductor plates; and toppling over the control circuit board to thereby receive the control circuit board in the housing (Aspect 6).
According to the aforementioned power distributor and connecting method, the control circuit board is supported in an erect state by the board support portion provided near the conductor plates in advance. Hence, the control circuit board can be easily connected to the conductor plates through a flexible wiring material without using a robot, a jig, or the like to hold the control circuit board. When the control circuit board is toppled over after the connection, the control circuit board can be received in the housing without any inconvenience.
As for a specific structure of the power distributor, when, for example, the housing is molded from an electrically insulating material around the conductor plates, the total structure of the power distributor can be simplified and the number of parts can be reduced greatly. Moreover, in this case, when configuration is made so that the board support portion is formed to be integrated with the housing, the control circuit board can be supported without increasing the number of parts (Aspect 2).
Further, as a specific structure for the board support portion, if there is provided a structure in which the board support portion has support members provided near a side wall of the housing so as to be erected, and in which an insertion space is formed between the side wall of the housing and each of the support members so that a lower end portion of the control circuit board in an erect state can be inserted into the insertion spaces (Aspect 3), the control circuit board can be supported by a simple structure using the side wall of the housing effectively.
Any structure may be used for the board support portion so long as the board support portion can support the control circuit board at least in an erect state. If the board support portion supports the control circuit board so that the control circuit board is rotatable between an erect position in which the control circuit board is erected with respect to the conductor plates and a toppled position in which the control circuit board is toppled over approximately in parallel with the conductor plates, the board support portion is more preferred (Aspect 4). In this configuration, after the control circuit board is connected to the conductor plates through the flexible wiring material in the condition that the control circuit board is supported in the erect posture by the board support portion, the control circuit board can be toppled over and received in the housing while making the control circuit board supported by the board support portion (in other words, without removing the control circuit board from the board support portion) (Aspect 7). Hence, working efficiency is improved more greatly.
For example, a structure for supporting axial portions protruded at left and right ends of the lower end portion of the control circuit board so that the control circuit board is rotatable around the axial portions is preferably used for the board support portion (Aspect 5).